Gülsen Öner

Measurement of pancreatic blood flow in dog by133Xe clearance technique

SummaryThe water/gas, plasma/gas, erythrocyte/gas and pancreas/gas partition coefficients of133Xe were measured at 37° C using dog tissues. The pancreas/blood partition coefficients were calculated from these figures and plotted as a function of hematocrit. The133Xe pancreas/blood partition coefficient in the normal range was 1.2 ml/g.Pancreatic blood flow was determined in each case by injecting the tracer into the pancreaticoduodenal artery (mean 106.8±30.4 ml/100 g/min). Pancreatic blood flows were also determined by injecting the tracer into the tissue of head, body and the tail of pancreas. The means of the results were 62.4±22.2, 85.7±35.6 and 67.1±26.4 ml/100 g/min respectively. The mean pancreatic blood flow obtained by intra-arterial injection was significantly different (P<0.05) from the results obtained by injecting133Xe into the head or tail, but was not statistically different from that of the body of pancreas. The results of the head, body and tail of pancreas were not significantly different from each other (P>0.05).

Calculation of net insulin secretion and pancreatic blood flow

SummaryUsing133Xe washout technique pancreas blood flow has been calculated. Injected the radio-tracer into a small branch of the pancreatico-duoodenal artery pancreatic blood flow rate was found 106.69±9.95 ml/100 g/min. Insulin concentrations of the peripheral and pancreatic veins have been determined and net insulin secretion have been calculated. Under our experimental conditions it was found 8.97±1.91 mU/100 g/min. The same parameters were calculated after injecting the nuclide into the head, corpus and tail of the pancreas separately and the results were compared to that of intra-arterial injection.This approach is proposed as a quantitative method of evaluating β cell function under various physiological and pathological conditions.

Pancreatic blood flow in hemorrhagic shock

Pancreatic blood flow rates were determined using a133Xe washout technique in a total of 40 dogs, 14 of which were used as a control group and the remaining 26 as the experimental group. The initial pancreatic blood flow rates of control group and of the experimental group were 85.1±10.1 ml/100g/min of pancreas/min and 81.1±5.4 ml/100g/min respectively. These values were not significantly different from each other (P>0.05). In the control group the blood flow was determined 3 times at 30 min intervals. These mean values were 73.0±9.4, 74.6±8.7, and 79.4 ±10.4 ml/100g/min respectively (P>0.05). The dogs in the experimental group were bled and the peripheral arterial blood pressure was reduced stepwise to 80, 50, and 30 mm Hg. At each level a 30 min of stabilization period the pancreatic blood flow rates were 49.8±3.7, 29.3±2.3 and 20.2±2.3 ml/100g/min respectively. These mean values were very significantly reduced compared to those of the control group, at 30 min (P<0.02), at 60 and 90 min (P>0.001). They were also very significantly different from their own initial values (P<0.001). the metabolic consequences of this reduction in pancreatic blood flow are discussed.